Hyperoxia-induced changes in morphometric parameters of postnatal neurogenic sites in rat

In literature many works address the effects of hypoxia exposure on postnatal neurogenesis but few data are available about hyperoxia effects, although high oxygen concentrations are frequently used for ventilation of premature newborns. Thus, the aim of the present study was to compare with controls the morphometrical parameters of the main neurogenic sites (subventricular zone and dentate gyrus) in newborn Sprague-Dawley rats exposed to 60% or 95% oxygen for the first 14 postnatal days. Six rats were studied for each of the three groups. The unbiased quantitative method of the optical disector was applied to analyze neuronal densities, nuclear volumes, and total neuron numbers of the subventricular zone and hippocampal dentate gyrus. Apoptosis (terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling, TUNEL) and proliferation (Ki67) were also studied. The subventricular zone of newborn rats exposed to 95% hyperoxia showed statistically significant higher volume (mean value ± coefficient of variation: 0.40 ± 0.20 mm3) than subventricular zone of rats raised in normoxia (0.20 ± 0.11 mm3) or 60% hyperoxia (0.26 ± 0.18 mm3). Total neuron number was also significantly higher in 95% hyperoxia while neuronal densities did not reach statistically significant differences. TUNEL showed increased apoptotic indexes in hyperoxic rats. The percentage of proliferating KI67 positive cells was also higher in hyperoxia. The dentate gyrus granular layer of the normoxic rats showed higher volume (0.65 ± 0.11 mm3) than both the hyperoxic groups (60% hyperoxia: 0.39 ± 0.14 mm3; 95% hyperoxia: 0.36 ± 0.16 mm3). Total neuron numbers of hyperoxic dentate gyrus were also significantly reduced; neuronal densities were not modified. Hyperoxia-exposed rats also showed higher apoptotic and proliferating indexes in the dentate gyrus. Hyperoxia exposure in the first postnatal period may affect the main neurogenic areas (subventricular zone and dentate gyrus) increasing apoptosis but also inducing a certain reparative response consisting of increased proliferation. In particular, the increased volume of the subventricular zone may be ascribed to compensatory neurogenic response to the hyperoxic damage. Conversely, the decreased volume of the dentate gyrus granular layer could derive by a non sufficient neurogenic response to counterbalance the hyperoxic neuronal injury

L-citrulline is protective in hyperoxic lung damage and improves matrix remodelling and alveolarization

Moderate hyperoxia alters alveolar and vascular lung morphogenesis. Nitric oxide (NO) and matrix metalloproteinases (MMP) have a crucial role in the homeostasis of the matrix and bronchoalveolar structure and may be regulated abnormally by exposure to hyperoxia. Disruption of vascular endothelial growth factor (VEGF)-NO signaling impairs vascular growth and contributes to hyperoxia-induced vascular disease in bronchopulmonary dysplasia (BPD). We hypothesize that L-citrulline, by raising the serum levels of L-arginine and enhancing endogenous NO synthesis, might attenuate hyperoxia-induced lung injury in an experimental model of BPD. Neonatal rats (1 day old) were exposed to 60% oxygen or room air for 14 days and administered L-citrulline or a vehicle (sham). Lung morphometry were performed; Serum was tested for arginine level; Matrix metalloproteinases2 (MMP2) gene expression, VEGF gene and protein expression and endothelial NO synthase (eNOS) protein expression were compared. Mean linear intercept was higher in the hyperoxia and sham groups when compared with the room air (RA) and L-citr+hyperoxia treated group (p<0.02). Secondary crests number was higher in L-citrulline treated and RA when compared to hyperoxia and sham group (p<0.02). L-Arginine level rose in the L-citrulline-treated group (p<0.05). L-citrulline did not affect MMP2 gene expression, but it regulated the MMP2 active protein, which rose in bronchoalveolar lavage fluid (p<0.05), presumably due to a post-transductional effect. Compared with RA controls, hyperoxia significantly decreased VEGF and eNOS protein expression. At the same time, an increased lung VEGF gene and protein expression (p<0.05) were also seen in the rats treated with L-citrulline. We conclude that: (i) hyperoxia decreases growth and disrupts VEGF-NO signaling of lung; (ii) the main effects of L-citrulline are an increased serum level of arginine, as a promoter and a substrate of the nitric oxide synthase; and (ii) a better alveolar growth and matrix control than in hyperoxia-induced lung damage seems promising

FAMILIES WITH PLURIDISABLED CHILDREN: THE PARENTAL POINT OF VIEW OF THEIR RELATIONSHIP WITH HEALTH AND SOCIAL SERVICES

Il contributo documenta un lavoro di ricerca qualitativa condotto con trenta famiglie che hanno un figlio con disabilit\ue0 complessa. Dopo una dissertazione introduttiva sulla terminologia scientifica utilizzata in letteratura per riferirsi all'area delle disabilit\ue0 complesse, gli autori sviluppano due sezioni: una prima, dove illustrano il modello del Family Center Care, con i riscontri presenti in letteratura sull'efficacia di un modello di cura che investe nella partnership tra professionisti e genitori, nonch\ue8 l'importanza della rete di prossimit\ue0 per il benessere familiare. Una seconda, dove presentano la ricerca sul campo che mette a fuoco i punti di forza e gli aspetti di criticit\ue0 della rete di cura pediatrica per i bambini con plurideficit. In questa parte si evidenzia soprattutto l'importanza di una gestione attenta della cosiddetta prima comunicazione, nonch\ue8 una gestione oculata della fase di transizione dall'ospedale alla presa in carico dei servizi territoriali. Emerge una non ancora soddisfacente qualit\ue0 della comunicazione dei professionisti verso la famiglia, con quest'ulltima che si racconta ancora troppo spesso disorientata nel processo di cura complessivo e, proprio perch\ue8 insoddisfatta dell'azione dei servizi, impegnata a trovare canali riabilitativi alternativi a quelli isituzionali, nell'idea che nuove cure intensive possano migliorare il quadro clinico del proprio figlio. Il contributo si chiude con alcune riflessioni complessive sulla qualit\ue0 dei percorsi di cura, con una sottilineatura circa la necessit\ue0 di promuovere processi co-partecipati all'interno dei servizi tra professionisti e genitori, quale presupposto di qualsiasi buona esperienza di presa in carico

Families with Pluridisabled Children: The Parental Point of View on their Relationship with Health and Social Services

Article, published in this excellent publisher, is important because it has an interdisciplinary approach very original and very rich. With great balance it brings together educational sciences, medicine, psychology, psychiatry. The effective mode helping to review the issues addressed with a new science and culture optical. The term \u201cpluridisabled children\u201d broadly denotes a diagnostic area which is referred to in the scientific literature using a range of terminology. The English-language literature predominantly uses the term PIMD (Profound Intellectual and Multiple Disabilities), while the Frenchlanguage literature prefers the word polyhandicap. Both definitions emphasize the coexistence of cognitive, motor, and sensory impairments. The Special Interest Research Group on Profound and Multiple Disabilities, a sub-organization of the International Association for the Scientific Study of Intellectual Disability (IASSID), highlights the key characteristic of such people: significant motor and intellectual impairments (Nakken and Vlaskamp, 2007

INTERVENTI AL LIMITE. BIOETICA DELLE TERAPIE INTENSIVE NEONATALI

Le esperienze maturate dal Comitato di Bioetica del Dipartimento di Pediatria di Padova, le risposte alle domande che sorgono in materia di intervento medico e mortalit\ue0 infantile, rianimazione dei neonati e patologie procurate dalle stesse tecniche impiegate per supportare le funzioni natali dei prematur